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<p class="header"><a class="header" href="intro.htm">Orbiter</a> &gt; <a class="header" href="mfd.htm">MFD</a> &gt; Orbit</p>

<h1>Orbit MFD</h1>

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<td width=33% align=center><a href="mfd_orbit_ctrl.htm">Controls</a></td>
<td width=33% align=center><a href="mfd_orbit_disp.htm">Display</a></td>
<td align=center><a href="mfd_orbit_cfg.htm">Config</a></td>
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<p>The Orbit MFD mode displays a list of elements and parameters which characterise the ship's orbit around a central body, as well as a graphical representation. In addition, a target object (ship, orbital station or moon) orbiting the same central body can be selected, whose orbital track and parameters will then be displayed as well.</p>

<p>The instrument shows the osculating orbits at the current epoch, i.e. the 2-body orbit corresponding to the vessel's current state vectors. The orbital parameters may change with time due to the influence of perturbing effects (additional gravity sources, distortions of the gravitational field due to nonspherical planet shape, atmospheric drag, thruster action, etc.)</p>

<p>The orbital elements can be displayed with respect to one of two frames of reference: ecliptic or equatorial. The plane of the ecliptic is defined by the Earth's orbital plane, and is useful for interplanetary flights. The equatorial plane is defined by the equator of the current reference object, and is useful for low orbital and surface-to-orbit operations. Use <kbd class="ctrl">Shift</kbd> <kbd>F</kbd> to switch between the two frames of reference. The current mode is displayed in the top line of the display (<i>Frm</i>).</p>

<p>The plane into which the graphical orbit displays are projected can be selected via <kbd class="ctrl">Shift</kbd> <kbd>P</kbd>. The current projection plane is indicated in the top right corner of the instrument (Prj). <i>ECL</i> or <i>EQU</i> project into the plane of the ecliptic or equator, respectively. <i>SHP</i> projects into the vessel's current orbital plane, and <i>TGT</i> projects into the target's current orbital plane, if a target is specified.</p>

<p><kbd class="ctrl">Shift</kbd> <kbd>T</kbd> opens a menu to specify a target object. Only targets which orbit around the current reference object will be accepted. The target display can be turned off with <kbd class="ctrl">Shift</kbd> <kbd>N</kbd>.</p>

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